The engine is known as the heart of the vehicle. During the engine operation, it generates extreme heat. Therefore, engine parts need to bear extreme heat and wear and tear due to that they may damage over time.
As the engine parts are damaged, you need engine overhauling. Most commonly, the engine overhaul is performed when the car engine parts have some severe problems.
The engine overhaul of your car engine has the ability to restore the dead engine. This article explains the engine overhaul meaning, causes, signs, and how to prevent it.
What is an Engine Overhaul?
An engine overhaul is a process of removing, stripping, checkup, cleaning, and repairing the faulty internal parts of the engine.
In the overhauling process, the technician removes the engine parts and then inspects the parts to find the problem. For example, if your engine piston, head gasket, camshaft, crankshaft, connecting rod, or bearing has been damaged, the technician repairs it.
For example, if your engine piston, head gasket, camshaft, crankshaft, connecting rod, or bearing has been damaged, the technician repairs it.
During this process, the mechanic also cleans the engine surface and its components to remove the collection of carbon that may reduce engine efficiency. One of the major advantages of overhaul is that it increases the service life and performance of your engine.
Sings of Engine Overhaul
One or more of the below-given common symptoms indicate that your engine overhaul is in need of an engine overhaul:
- White exhaust smoke
- High oil consumption
- Engine overheating
- Black exhaust smoke
- Reduction in engine performance
- Strange noises from the engine
- Coolant level
- Check engine light
- Oil sludge
- Compression loss
- Dropped valve
- Rough idle
1) White Exhaust Smoke
As the engine oil or coolant enters the cylinder, it mixes and burns with the air-fuel mixture; due to that, your engine emits white smoke from the vehicle tailpipe. This white smoke indicates that your vehicle has a damaged gasket or piston ring.
As you continuously observe the white smoke, drive your vehicle to a mechanic and ask for an engine overhaul. However, do not confuse it with the white smoke that the vehicle emits at the initial start-up.
2) High Oil Consumption
One of the major signs that your car engine requires an overhaul is extreme oil consumption. If your engine oil level goes down very quickly or the low oil pressure warning light comes on, it means that your engine has a leaky or damaged part.
A damaged head gasket, a damaged hose, or a damaged piston ring can cause a quick reduction in the engine oil level.
Read More: Low Engine Oil Symptoms and Causes
3) Engine Overheating
Engine overheating means that your cooling system is not working properly. Your engine most commonly overheats due to a faulty water pump, leaky hoses, insufficient engine oil, insufficient coolant, a damaged combustion chamber, or a leaky radiator. It may also cause due to leaky head gaskets.
As the head gasket leaks, the engine oil starts burning into the combustion chamber, which leads to many mechanical problems.
The car dashboard also has a temperature gauge that indicates the engine temperature. If this gauge goes into the red zone, you need to contact a mechanic for the engine overhauling.
Read More: Engine Overheating Symptoms and Causes
4) Black Exhaust Smoke
The engine emits black smoke due to carbon deposits on the intake valve and piston. Constant emission of black smoke usually indicates that the engine needs an overhaul. It generates problems in air-fuel mixture combustion. As a result, engine performance and fuel efficiency are reduced.
During the combustion process, especially when accelerating the vehicle, the accumulated carbon escapes from the exhaust gases in the form of black smoke. This build-up of carbon can lead to severe damage to the engine.
Read More: How to Put Water in Car Radiator
5) Reduction in Engine Performance
Engine misfiring issues occur when the air/fuel ratio in the engine cylinders is incorrect or when the spark plug doesn’t properly ignite the air/fuel mixture.
The engine misfiring reduces the acceleration of the vehicle and reduces engine performance. If the cause of the problem is a worn spark plug, it can be easily replaced. However, a worn piston or piston ring can also lead to engine misfiring, which requires an engine overhaul.
Read More: Bad Spark Plug Symptoms and Causes
6) Strange Noises from the Engine
A strange engine noise usually means that your engine has a broken, cracked, loose, or worn part. The knocking noise may represent that there is excessive clearance between the piston rod and the crankshaft or that there is a problem with the valve train. This unpleasant noise may also cause due to a damaged piston ring.
If your engine makes unusual noises, it is recommended to consult a professional.
7) Coolant Level
A quick reduction in the coolant level is a clear sign that your engine has a leaky part and it needs an overhaul.
The leaky head gasket, damaged piston ring, or cracked engine cylinder may lead to a quick reduction of the coolant level.
Read More: Low Coolant Level Symptoms and Causes
8) Check Engine Light
The latest vehicle models contain a check engine light. When something goes bad with your engine, the check engine light starts to illuminate. This warning light may also indicate a severe engine issue.
A faulty spark plug, a damaged fuel injector, a low coolant level, insufficient engine oil, a damaged engine cylinder, or a faulty engine sensor are the most common causes of the check engine light illumination.
Read More: Causes of Check Engine Light Illumination
9) Oil Sludge
The oil sludge on the fuel cap or dipstick is one of the clear signs of an engine issue. The oil sludge may accumulate due to one or more of the following causes:
- Coolants
- Wrong engine oil
- Old engine
- Grime
The oil sludge accumulation shows that the parts of your engine are not lubricated properly.
As you observe the dark oil deposit around your engine, it may indicate that your engine may need an overhauling. However, the accumulated oil sludge may lead to different issues, such as poor engine performance or poor fuel economy.
10) Compression Loss
Compression loss is a situation commonly associated with reduced performance and a decrease in power. An engine coolant or fuel leak may lead to engine oil contamination, leading to a higher oil level in the crankcase.
However, the compression loss often suggests leaks occurring elsewhere within the engine as well. An engine cylinder is usually leaked due to excessively worn components that require replacement. Deteriorating performance and a leaking engine cylinder signal that an overhaul is necessary.
11) Dropped Valve
A dropped valve takes place if the valve head of your vehicle engine becomes bent and severed, leading it to fall into the engine cylinder. This event can inflict significant damage on the whole engine.
If you face dropped valve issue, you need to replace one or more of the below-given engine parts:
- Valves
- Cylinder
- Piston
12) Rough Idle
Your engine may need overhauling as the diesel engine of your vehicle produces different issues during idling or while shutting off the engine.
If your car produces a bouncing motion upon stopping, it signifies wear and tear. Additionally, if the vehicle engine fails to shut down as you attempt to turn it off, it could suggest oil has infiltrated the combustor.
Read More: How to Flush an Engine
Causes of Engine Overhaul
Following are the major issues that may need the engine overhaul:
- Overheating
- Leaked hoses
- Abnormal combustion
- Worn piston or piston ring
- Poor maintenance
- Cracked engine block
- Low engine oil
1) Overheating
The engine overheats when the cooling system doesn’t properly cool the engine moving parts. The engine overheats due to a faulty radiator, faulty water pump, cracked cylinder, or blown head gasket. The overheating badly harms the parts of the engine and reduces the engine performance.
Solution: Ensure the proper maintenance of the engine parts and timely change of the parts.
2) Leaked Hoses
Leaky hoses are one of the major causes of engine overhaul. The hoses connect the water pump to the engine and the engine to the radiator. The coolant circulates inside the hoses. The hoses are responsible for properly circulating the coolant.
As the hoses become damaged, they can’t properly circulate the coolant, which leads to engine overheating.
Solution: Properly maintain the hose and immediately replace the leaked or damaged hoses.
3) Abnormal Combustion
Abnormal combustion in the engine combustion chamber can generate unnecessary heat and pressure in the combustion chamber, which can crack the engine block or other internal parts.
Due to abnormal combustion, the vehicle may also generate a knocking noise. This is usually caused by a malfunction in the exhaust gas recirculation system. The EGR system helps the engine to guarantee the correct air-fuel mixture. But fuel with a low octane number, high engine operating temperatures, incorrect spark plugs, or poor ignition timing may also cause abnormal combustion.
Solution: Ensure proper maintenance and inspection of your engine parts.
4) Worn Piston or Piston Ring
The worn or damaged piston ring is a major cause of engine overhaul. The worn piston ring may also cause oil leaks into the combustion chamber.
Solution: Replace the worn piston or piston ring.
5) Poor Maintenance
The use of low-quality engine oil or poor maintenance may cause the sludge and deposits to accumulate inside the engine. The cumulation of the contaminants inside the engine may lead to poor oil pressure, engine overheating, and potential engine damage.
Solution: Ensure proper maintenance of your engine according to the manufacturer’s recommendation.
6) Cracked Engine Block
A blown head gasket, engine overheating, or some other issues may lead to engine block damage. If you don’t repair a damaged or cracked engine block on time, it may lead to the complete failure of the engine.
Solution: Replace the damaged engine block immediately
7) Low Engine Oil
Your engine requires a sufficient supply of oil to work efficiently. The engine oil reduces the friction between the engine’s moving parts (such as the crankshaft, connecting rod, piston, and crankcase) and prevents them from overheating or damage.
Insufficient engine oil may lead to the failure of different engine parts and may also lead to the complete failure of the engine.
Solution: Ensure a sufficient supply of engine oil.
How to Prevent Engine Overhauling?
- Ensure the sufficient level of engine oil to properly lubricate the engine parts
- Ensure a proper supply of the engine coolant
- Ensure proper maintenance of your engine according to the manufacturer’s recommendation
- Replace the damaged parts on time
- Replace or repair the damaged or leaked engine hoses as soon as possible
- Replace the faulty radiator
- If your engine starts to overheat, fix it quickly
- Replace the cracked or damaged engine cylinder
- Ensure proper combustion of the air-fuel mixture
Advantages of Engine Overhauling
- One of the major advantages of engine overhauling is that it helps to improve engine performance
- This process improves fuel efficiency and power out
- When you replace the damaged or faulty parts of your engine during overhauling, it may significantly extend the service life of your engine.
- This process permits the vehicle’s owner to fix minor problems before they become major issues, decreasing the chances of catastrophic engine failure and potentially saving you significant time and money in the long run.
- Overhauling may play a big role in improving the fuel economy by fixing problems (such as damaged spark plugs, dirty fuel injectors, worn piston rings, and leaking valves) that may cause poor combustion and poor fuel economy.
- The repair or replacement of the damaged engine parts may assist in reducing harmful emissions and promote a cleaner environment and also ensure obedience to increasingly stringent emissions regulations.
- However, overhauling may be a costly process, but it is usually more cost-effective than replacing the entire engine or vehicle, particularly if the remaining parts of the vehicle are in good condition.
- The overhauling may increase your car’s resale value.
Disadvantages of Engine Overhauling
- Engine overhauling may be costly, especially if it involves extensive repairs or replacing an expensive component such as a crankshaft or engine cylinder.
- The overhaul process takes a lot of time
- In some conditions, the engine overhauling may not address all the problems within an engine, mainly if specific problems are not instantly apparent during the inspection.
- This process needs a skilled professional with specialized knowledge and experience, which may be hard to find, especially in remote or rural areas.
- Your engine overhauling can void the warranty of your engine or vehicle.
- The process of reassembling, repairing, or disassembling the engine may be hard, and errors or oversights during the overhauling may cause further issues or even engine failure.
FAQ Section
What is the purpose of an engine overhaul?
The main purpose of engine overhauling is to restore the reliability, fuel economy, and performance of the engine by disassembling, repairing, cleaning, inspecting, and reassembling it. This process helps to repair or replace worn or damaged parts and fix problems that may cause engine failure, eventually improving the service life of the engine and maintaining its overall functionality.
When should I overhaul my engine?
You should overhaul your engine when you observe a clear reduction in the engine performance, including excessive oil consumption, engine overheating, engine misfiring, unusual noise, poor acceleration, poor fuel economy, or reduced power. Also, if you notice extreme wear or damage to internal parts, it may be time for an overhaul.
How long does an engine last after overhaul?
The service life of the engine after overhauling varies according to different factors, including the engine’s make and model, the quality of the work, the extent of the overhaul, and how well the engine is maintained after overhauling.
If you or your mechanic perform the overhauling properly and the engine is well-maintained, it may definitely last for tens of thousands to hundreds of thousands of miles. However, the proper inspection and maintenance of the engine are very important to achieve longevity and optimal performance of the engine.
What are the types of overhauling?
- Engine top overhaul
- Engine complete overhaul
What are the problems that lead to engine overhauling?
- Overheating
- Leaked hoses
- Abnormal combustion
- Worn piston or piston ring
- Poor maintenance
- Cracked engine block
- Low engine oil